Biotin derivatives and processes of preparing the same



Patented Jan. 16, 1951 BIOTIN DERIVATIVES AND PROCESSES OF PREPARING THESAME Donald E. Wolf, Franklin Township, Somerset County, and KarlFolkers, Plainfield, N. J assignors to Merck & 00., Inc., Rahway, N. J acorporation of New Jersey No Drawing. Application July 1, 1947, SerialNo. 758,486

This invention is concerned generally with Claims. (Cl. 260-309) novelchemical compounds and processes of preparing the same. Moreparticularly, it relates to novel biotin derivatives which possessphysiological activity as growth promoting factors for microorganisms.

The novel chemical compounds forming the subject matter of the presentinvention are the biotin amides and biotin aromatic amines. It has beenestablished with reasonable certainty that these novel compounds havethe following structural formula:

appease H-gC-S-JJH(CH;)OONHR wherein R represents hydrogen, aryl andaralkyl substituents.

In accordance with the present invention these new compounds may beprepared by reacting ammonia, arylamines and aralkylamines withcompounds represented by the formula:

m l-c ique HG---(:ZH HflL-S-OH-(GHzhCOR wherein R represents halogen andalkoxy substituents.

Starting materials of the above formula wherein R is a halogensubstituent are fully defined by the name biotin acid halides whereinthecarboxyl groups are converted to acid halide groups. These biotinacid halide compounds can be prepared by reacting biotin with phosphorushalides, sulfuryl halides and thionyl halides. This process and theproducts thereby obtained are fully disclosed and claimed in a copendingjoint application by the present inventors, Folkers, Mozingo, and Wolf,Serial No. 554,460, filed September 16, 1944, now U. S. Patent No.2,442,681, issued June 1, 1948.

Compounds of the above formula wherein R represents alkoxy substituentsare fully defined as the biotin alkyl esters and dl-biotinalkyl esters.I The amine compounds, which may be employed as reactants in ourinvention, includeammonia, arylamines, such as aniline and pamino-.

benzoic acid, and aralkylamines such as benzylamine. p In carrying outthe process of the present invention a biotin acid halide or a biotinester is reacted with an arylamine, an aralkylamine or ammonia. It ispreferable to employ an excess of the amine which may also act as acondensing agent. In the event that the amine is a solid, a condensingagent such as pyridine or sodium hydroxide may be employed. The reactionis preferably conducted at room temperature. When condensation iscomplete the crystals of the biotin amine compound are removed. While asubstantially pure product is recovered by merely filtering oif thewhite crystalline solid and washing with water, further purification maybe necessary or desirable. This can be accomplished by recrystallizingthe product from methanol.

The following examples illustrate a method of carrying out the presentinvention but it is to be understood that these examples are given byway of illustration and not of limitation.

Example 1 About 25 mg. of biotin was dissolved in 7 drops of thionylchloride at room temperature. After five minutes the excess thionylchloride was removed by evaporation in vacuo. The white crystallinebiotin acid chloride obtained was dissolved in 2 ml. of concentratedammonium hydroxide at room temperature and biotin amide separated fromsolution as a nearly white solid.

Recrystallization of the product from methanol resulted in pure biotinamide melting at 241-247 C.

Anal. calcd. for CioHrzNsOzsl C, 49.36; H, 7.04;

C, 49.71; H, 7.11; N, 16.79.

Example 2 Example 3 About '73 mg. of dl-biotin was treated with 1 ml. ofthionyl chloride at room temperature. The excess thionyl chloride wasremoved by evaporationin vacuo leaving dlbiotin acid chlorideas a clearoil. The dl-biotin acid chloride was treat ed with concentrated ammoniumhydroxide and the crystalline dl-biotin amide was filtered from themixture. The dl-biotin amide was recrystallized from methanol. Thisproduct had a melting point of 265-267" C.

Anal. calcd. for C1oH1'7N3O2S: C, 49.36; H, 7.04;

Found: C, 48.88; H, 6.67; N, 16.94.

Example 4 Example -5 100 mg. of biotin was converted to biotin acidchloride by treating it with thionyl chloride as described in Examples 1and 2. 2 cc. of aniline was added to the biotin acid chloride, and thereaction allowed to stand for approximately 72 hours. The excess ofaniline was evaporated in vacuo leaving a solid residue. The product,biotinanilide, was washed with 0.1 N hydrochloric acid, 2% sodiumbicarbonate, and water to remove unreacted starting material. Thebiotinanilide was recrystallized from methanol, giving a whitesolidmelting between 206-210 C.

Anal. calcd. for C16H21N302SZ C, 60.16; H, 6.63;

Found: C, 59.48; H, 6.81; N, 13.40.

Example 6 N hydrochloric acid, 2% sodium bicarbonate solution, andwater. The biotin benzylamide collected weighed 16.8 mg. and was a whitesolid belting at 122-125 C.

Anal. calcd. for C17H23N302S: C, 61.24; H, 6.95;

Found: C, 60.47; H, 7.09; N, 11.76.

Example 7 About 100 mg. of biotin was converted to biotin acid chlorideby treating it with thionyl chloride. To the biotin acid chloride thusobtained was added 500 mg. of p-aminobenzoic acid dissolved in 2.5 Nsodium hydroxide at 0 C. The reaction mixture was stirred until allsolid had dissolved and then acidified with hydrochloric acid whichcaused precipitation of p(biotinylamino) benzoic acid as a white solid.The mixture was filtered, and the solid washed with water. This productwasre'c'rystallized from methanol in the form of white crystals.

Anal calcd. for C17H21N3O4S: C, 56.18; H, 5.83;

Found: C, 55.63; H, 5.8-8; N, 11.63.

Modifications may be made in carrying out the present invention withoutdeparting from the spirit and scope thereof and the invention is to belimited only by the appended claims.

4 We claim: 1. A compound of the formula wherein R is selected from thegroup consisting of hydrogen, aryl, and aralkyl and carboxyarylsubstituents.

. Biotin amide.

. dl-Biotin amide.

. Biotinanilide Biotin benzylamide.

. p(Biotiny1amino) -benzoic acid.

The process that comprises reacting a substance selected from the classconsisting of ammonia, arylamines, aralkylamines and carboxyarylamineswith a compound of the formula HzCSCH-(CH);COR wherein R is selectedfrom the group consisting of halogen and alkoxy substituents to form thecorresponding biotin amine compound.

8. The process that comprises reacting ammonia with a compound of theformula HzC S( 1H-(CHz)4COR wherein R is selected from the groupconsisting of halogen and. alkoxy substituents to form biotin amide.

9. The process that comprises reacting biotin acid halide with ammoniahydroxide to form biotin amide.

10. The process that comprises reacting d]- biotin acid halide withammonium hydroxide to form dl-biotin amide.

11. The process that comprises reacting biotin methyl ester withammonium hydroxide to form biotin amide.

12. The process that comprises reacting d1-' biotin methyl ester withammonium hydroxide to form dl-biotin amide.

13. The process that comprises reacting biotin acid halide with anilineto form biotinanilide,

14. The process that comprises reacting biotin acid halide withbenzylamine to form biotin benzylamide.

15. The process that comprises reacting biotin acid halide withp-aminobenzoic acid in the presence of sodium hydroxide, and acidifyingthe resulting mixture with an inorganic acid to precipitatep(biotinylaminobenzoic)acid.

DONALD E. WOLF. KARL FOLKERS.

REFERENCES CITED The following references are of record in the file ofthis patent: Y 4

UNITED STATES PATENTS OTHER REFERENCES Du Vigneaud: J. A. c. s., vol.64, pp. 188-189. Hofmann: J. A. C. 8., vol. 66, pp. 51-53.

1. A COMPOUND OF THE FORMULA
 7. THE PROCESS THAT COMPRISES REACTING ASUBSTANCE SELECTED FROM THE CLASS CONSISTING OF AMMONIA, ARYLAMINE,ARALKYLAMINES AND CARBOXYARYLAMINES WITH A COMPOUND OF THE FORMULA